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Emerald Ash Borer in Colorado

Denver Colorado, 09/28/13:

The Colorado Department of Agriculture confirmed today that the Emerald Ash Borer was found in Boulder County. This destructive pest has caused billions in damaged across the Ohio, Michigan, and Illinois. We have been following this insect and knew this would happen, but hoped it wouldn’t be this soon.

Our team of certified Arborists are ready to help you protect your Ash trees.
To learn more, call 303.232.0666 or send us an online estimate request »

Emerald Ash Borer in Colorado
Photos from: &

“It is one of the most destructive, invasive species the U.S. has faced,” said John Kaltenbach, pest survey coordinator for the agriculture department.

This pest is nearly 100 percent fatal to Ash trees which are plentiful in Denver because they provide shade, grow quickly and they do well despite in Colorado’s climate.

The Emerald Ash Borer is a small, but very destructive beetle. An adult beetle easily fits on the size of a penny, and is metallic green, with a slender body that measures half an inch long. Native to eastern Asia and China, the beetle most likely arrived in North America hidden in wooden crates to ship goods. They first arrived in Michigan, where it took about  12 years before anyone detected and identified the beetles. The beetle is behind the death and decline of millions of Ash trees in the eastern states. And now, much to our dismay, this pest has arrived in Colorado.

Signs and Symptoms:
It is not easy to tell if an Ash tree is infested with the Emerald Ash Borer because the tree decline is gradual. Early symptoms may include dead branches near the top of the tree, or wild, leafy shoots growing out from it’s lower trunk. D-shaped exit holes and bark splits exposing S-shaped tunnels may also be seen.

If a tree is infested with the beetle, the tree will die and will need to be removed to help prevent the menace from spreading to other trees.

"D-shaped" exit holes and woodpecker damage  on the trunk indicate an EAB infestation. Photo from:
“D-shaped” exit holes and woodpecker damage
on the trunk indicate an EAB infestation. Photo from:

Since these pests have been identified in Boulder, Colorado, it is important to start protecting your Ash trees. Adult Emerald Ash Borers can fly from a half a mile up to several miles to infest new trees if the conditions are right.

There is hope! Ash tree treatments include systemic and topical insecticides. For larger Ash Trees, Mountain High Tree recommends an insecticide application that is injected directly into the trunk of the tree. Injections are more eco-friendly, because unlike spraying or soil applications, the pesticide is injected directly into the tree, limiting exposure to your family, the applicator and the environment. Our Arborists are ready to help you protect your Ash trees. Call 303.232.0666 or send us an online estimate request » and we’ll come out and recommend a plan for the best protection of your Ash trees.

Learn more about Insect and Disease Control here »